A method and device for estimating remaining discharge energy of a battery

Abstract

The present application provides a method and device for estimating the remaining discharge energy of a battery. The method includes: obtaining the maximum available capacity of the battery to be estimated at the current temperature, the current state of charge (SOC) of the battery to be estimated, the depth of discharge (DOD) range allowed for the battery to be estimated under the current aging state, and the open-circuit voltage curve of the battery to be estimated at room temperature; calculating the theoretical remaining energy state of the battery according to the current SOC, DOD range, maximum available capacity of the battery, and the open-circuit voltage curve; obtaining the effective energy utilization efficiency of the battery to be estimated under the current working condition; and correcting the theoretical remaining energy state of the battery according to the effective energy utilization efficiency of the battery to obtain the actual remaining energy state of the battery. It can be seen that the method and device can adapt to the changes of the battery with temperature and load conditions, so as to quickly and accurately estimate the remaining discharge energy of the battery, which is beneficial to improving the energy management efficiency of the battery.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and in particular, to a method and device for estimating the remaining discharge energy of a battery. Background Art

[0002] At present, with the progress and development of technology, electric vehicles have gradually become popular, and people's attention to the mileage of electric vehicles has also gradually increased. Due to the limited energy density and power density of the battery in electric vehicles, and at the same time being restricted by the charging infrastructure, it is easy to cause "range anxiety" for users. The existing methods for estimating the remaining discharge energy of a battery usually measure a reference discharge energy SOE table based on a standard discharge condition (such as a 25°C, 1 / 3C constant current discharge condition), and then in actual application, calculate a correction coefficient according to the current temperature, current, and aging state, and simply multiply it by the result of looking up the table. However, it is found in practice that the existing methods cannot adapt to the changes of the battery with temperature and load conditions, so they cannot accurately estimate the remaining discharge energy of the battery, thereby reducing the energy management efficiency of the battery. Summary of the Invention

[0003] The purpose of the embodiments of the present application is to provide a method and device for estimating the remaining discharge energy of a battery, which can adapt to the changes of the battery with temperature and load conditions, so as to quickly and accurately estimate the remaining discharge energy of the battery, and is beneficial to improving the energy management efficiency of the battery.

[0004] The first aspect of the embodiments of the present application provides a method for estimating the remaining discharge energy of a battery, including:

[0005] Obtain the maximum available capacity of the battery to be estimated at the current temperature, the current battery SOC of the battery to be estimated, the DOD range allowed for the battery to be estimated to operate in the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature;

[0006] Calculate the theoretical remaining energy state of the battery according to the current battery SOC, the DOD range, the maximum available capacity of the battery, and the battery open-circuit voltage curve;

[0007] Obtain the battery effective energy utilization efficiency of the battery to be estimated under the current working condition;

[0008] Correct the theoretical remaining energy state of the battery according to the battery effective energy utilization efficiency to obtain the actual remaining energy state of the battery.

[0009] In the above implementation process, the method can preferentially obtain the maximum available capacity of the battery to be estimated at the current temperature, the current battery SOC of the battery to be estimated, the DOD range allowed for operation of the battery to be estimated in the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature; then, according to the current battery SOC, DOD range, maximum available capacity of the battery, and the battery open-circuit voltage curve, calculate the theoretical remaining energy state of the battery; then, obtain the battery effective energy utilization efficiency of the battery to be estimated under the current working condition; finally, correct the theoretical remaining energy state of the battery according to the battery effective energy utilization efficiency to obtain the actual remaining energy state of the battery. It can be seen that the method can adapt to the changes of the battery with temperature and load conditions, so as to quickly and accurately estimate the remaining discharge energy of the battery, which is beneficial to improving the energy management efficiency of the battery.

[0010] Further, the obtaining of the maximum available capacity of the battery to be estimated at the current temperature, the current battery SOC of the battery to be estimated, the DOD range allowed for operation of the battery to be estimated in the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature includes:

[0011] Obtain the current temperature of the battery to be estimated, the current battery SOC of the battery to be estimated, the DOD range allowed for operation of the battery to be estimated in the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature;

[0012] Obtain the maximum available capacity of the battery at the current temperature according to the preset battery capacity table.

[0013] Further, the calculating of the theoretical remaining energy state of the battery according to the current battery SOC, the DOD range, the maximum available capacity of the battery, and the battery open-circuit voltage curve includes:

[0014] Perform area integration calculation on the battery open-circuit voltage curve according to the current battery SOC, the DOD range, and the maximum available capacity of the battery to obtain the theoretical maximum discharge energy and the theoretical remaining available discharge energy;

[0015] Calculate the theoretical remaining energy state of the battery according to the theoretical maximum discharge energy and the theoretical remaining available discharge energy.

[0016] Further, the obtaining of the battery effective energy utilization efficiency of the battery to be estimated under the current working condition includes:

[0017] Obtain the second-order battery equivalent circuit model of the battery to be estimated under the current working condition and the preset first-order inertial filtering algorithm;

[0018] Calculate the actual available power output by the battery and the Joule heat power consumed by the battery internal resistance according to the second-order battery equivalent circuit model;

[0019] Calculate the battery effective energy utilization efficiency under the current working condition according to the first-order inertial filtering algorithm, the actual available power output by the battery, and the Joule heat power consumed by the battery internal resistance.

[0020] Further, calculating the battery effective energy utilization efficiency under the current working condition according to the first-order inertial filtering algorithm, the actual available power output by the battery, and the Joule heat power consumed by the battery internal resistance includes:

[0021] Perform filtering processing on the actual available power output by the battery through the first-order inertial filtering algorithm to obtain the filtered actual available power, and perform filtering processing on the Joule heat power consumed by the battery internal resistance through the first-order inertial filtering algorithm to obtain the filtered Joule heat power;

[0022] Calculate the battery effective energy utilization efficiency under the current working condition according to the filtered actual available power and the filtered Joule heat power.

[0023] The second aspect of the embodiments of the present application provides a device for estimating the remaining discharge energy of a battery. The device for estimating the remaining discharge energy of a battery includes:

[0024] A first acquisition unit, configured to acquire the maximum available capacity of the battery to be estimated at the current temperature, the current battery SOC of the battery to be estimated, the DOD range allowed for operation of the battery to be estimated in the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature;

[0025] A calculation unit, configured to calculate the theoretical remaining energy state of the battery according to the current battery SOC, the DOD range, the maximum available capacity of the battery, and the battery open-circuit voltage curve;

[0026] A second acquisition unit, configured to acquire the battery effective energy utilization efficiency of the battery to be estimated under the current working condition;

[0027] A correction unit, configured to correct the theoretical remaining energy state of the battery according to the battery effective energy utilization efficiency to obtain the actual remaining energy state of the battery.

[0028] In the above implementation process, the device can obtain the maximum available battery capacity of the battery to be estimated at the current temperature, the current battery SOC of the battery to be estimated, the DOD range allowed for operation of the battery to be estimated in the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature through the first acquisition unit; calculate the theoretical remaining energy state of the battery according to the current battery SOC, DOD range, maximum available battery capacity, and battery open-circuit voltage curve through the calculation unit; obtain the battery effective energy utilization efficiency of the battery to be estimated under the current working condition through the second acquisition unit; and then correct the theoretical remaining energy state of the battery according to the battery effective energy utilization efficiency through the correction unit to obtain the actual remaining energy state of the battery. It can be seen that the device can adapt to the changes of the battery with temperature and load conditions, so as to quickly and accurately estimate the remaining discharge energy of the battery, which is beneficial to improving the energy management efficiency of the battery.

[0029] Further, the first acquisition unit includes:

[0030] The first acquisition subunit is used to acquire the current temperature of the battery to be estimated, the current battery SOC of the battery to be estimated, the DOD range allowed for operation of the battery to be estimated in the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature;

[0031] The second acquisition subunit is used to acquire the maximum available battery capacity at the current temperature according to a preset battery capacity table.

[0032] Further, the calculation unit includes:

[0033] The first calculation subunit is used to perform area integration calculation on the battery open-circuit voltage curve according to the current battery SOC, the DOD range, and the maximum available battery capacity to obtain the theoretical maximum discharge energy and the theoretical remaining available discharge energy;

[0034] The second calculation subunit is used to calculate the theoretical remaining energy state of the battery according to the theoretical maximum discharge energy and the theoretical remaining available discharge energy.

[0035] Further, the second acquisition unit includes:

[0036] The third acquisition subunit is used to acquire the second-order battery equivalent circuit model of the battery to be estimated under the current working condition and a preset first-order inertial filtering algorithm;

[0037] The third calculation subunit is used to calculate the actual available power output by the battery and the Joule heat power consumed by the battery internal resistance according to the second-order battery equivalent circuit model;

[0038] The third calculation subunit is further configured to calculate the effective energy utilization efficiency of the battery under the current working condition according to the first-order inertial filtering algorithm, the actual available power output by the battery, and the joule heat power consumed by the internal resistance of the battery.

[0039] Further, the third calculation subunit includes:

[0040] A filtering module, configured to filter the actual available power output by the battery through the first-order inertial filtering algorithm to obtain the filtered actual available power, and filter the joule heat power consumed by the internal resistance of the battery through the first-order inertial filtering algorithm to obtain the filtered joule heat power;

[0041] A calculation module, configured to calculate the effective energy utilization efficiency of the battery under the current working condition according to the filtered actual available power and the filtered joule heat power.

[0042] A third aspect of the embodiments of the present application provides an electronic device, including a memory and a processor, where the memory is used to store a computer program, and the processor runs the computer program to enable the electronic device to execute the battery remaining discharge energy estimation method according to any one of the first aspects of the embodiments of the present application.

[0043] A fourth aspect of the embodiments of the present application provides a computer-readable storage medium, which stores computer program instructions. When the computer program instructions are read and run by a processor, the battery remaining discharge energy estimation method according to any one of the first aspects of the embodiments of the present application is executed. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required to be used in the embodiments of the present application. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0045] Figure 1 It is a schematic flowchart of a method for estimating the remaining discharge energy of a battery provided by an embodiment of the present application;

[0046] Figure 2 It is a schematic flowchart of another method for estimating the remaining discharge energy of a battery provided by an embodiment of the present application;

[0047] Figure 3 It is a schematic structural diagram of a device for estimating the remaining discharge energy of a battery provided by an embodiment of the present application;

[0048] Figure 4This is a schematic structural diagram of another battery remaining discharge energy estimation device provided by an embodiment of the present application. Detailed implementation manners

[0049] Next, the technical solutions in the embodiments of the present application will be described with reference to the accompanying drawings in the embodiments of the present application.

[0050] It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of the present application, the terms "first", "second", etc. are only used for differential description and cannot be construed as indicating or implying relative importance.

[0051] Embodiment 1

[0052] Please refer to Figure 1 , Figure 1 This is a schematic flow chart of a method for estimating the remaining discharge energy of a battery provided for this embodiment. Among them, the method for estimating the remaining discharge energy of the battery includes:

[0053] S101. Obtain the maximum available capacity of the battery to be estimated at the current temperature, the current battery SOC of the battery to be estimated, the DOD range allowed for operation of the battery to be estimated in the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature.

[0054] S102. Calculate the theoretical remaining energy state of the battery according to the current battery SOC, DOD range, maximum available capacity of the battery, and battery open-circuit voltage curve.

[0055] S103. Obtain the battery effective energy utilization efficiency of the battery to be estimated under the current working condition.

[0056] S104. Correct the theoretical remaining energy state of the battery according to the battery effective energy utilization efficiency to obtain the actual remaining energy state of the battery.

[0057] For example, the method can be implemented through the following steps:

[0058] (1) Obtain the SOC of the current battery, the allowed operating DOD range (SOC max and SOC min ) in the current aging state, and the open-circuit voltage SOC-OCV curve of the battery at room temperature.

[0059] (2) Obtain the maximum available capacity C max of the battery at the current temperature by looking up the capacity table according to the current temperature.

[0060] (3) According to the current SOC, DOD range (SOC maxand SOC min ) and the maximum available capacity C at the current temperature max Integrate the area of the battery open-circuit voltage curve to obtain the theoretical maximum discharge energy E max and the theoretical remaining available discharge energy E re , then the theoretical remaining energy state SOE of the battery pre = E re / E max .

[0061] (4) Estimate the effective energy utilization efficiency K of the battery under the current working condition according to the second-order battery equivalent circuit model and the first-order inertial filtering algorithm e .

[0062] (5) Use the estimated effective energy utilization efficiency K e to correct the theoretical remaining energy state SOE pre , and obtain the actual remaining energy state SOE of the battery under the current temperature and working condition act = K e * SOE pre .

[0063] In this embodiment, the execution subject of this method can be a computing device such as a computer or a server, and no limitation is made in this embodiment

[0064] In this embodiment, the execution subject of this method can also be a smart device such as a smart phone or a tablet computer, and no limitation is made in this embodiment

[0065] It can be seen that implementing the battery remaining discharge energy estimation method described in this embodiment can consider the influence of the actual temperature and working condition on the dischargeable energy of the battery; specifically, this method can accurately estimate and realize the actual remaining available energy state of the battery by combining the estimation of the theoretical remaining energy state obtained by integrating the area of the battery SOC-OCV curve and the influence of the actual temperature working condition on the energy effective utilization rate, so as to simplify the engineering application

[0066] Embodiment 2

[0067] Please refer to Figure 2 , Figure 2 which is a schematic flow chart of a battery remaining discharge energy estimation method provided in this embodiment. Among them, the battery remaining discharge energy estimation method includes

[0068] S201. Obtain the current temperature of the battery to be estimated, the current battery SOC of the battery to be estimated, the DOD range allowed for the battery to be estimated to operate under the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature

[0069] S202. Obtain the maximum available battery capacity at the current temperature according to a preset battery capacity table.

[0070] S203. Perform area integration calculation on the battery open-circuit voltage curve based on the current battery SOC, DOD range, and the maximum available battery capacity to obtain the theoretical maximum discharge energy and the theoretical remaining available discharge energy.

[0071] S204. Calculate the theoretical remaining energy state of the battery based on the theoretical maximum discharge energy and the theoretical remaining available discharge energy.

[0072] In this embodiment, the method can estimate the theoretical remaining energy state based on the area integration of the battery SOC-OCV curve. According to the actual SOC of the current battery, the allowable operating DOD range (SOC max and SOC min ) under the current aging state, and the open-circuit voltage SOC-OCV curve of the battery at room temperature, by integrating the curve area, we get:

[0073]

[0074]

[0075] For the practical application of the in-vehicle battery management system (BMS), the above area integration is discretized:

[0076] Let the minimum SOC integration step size be SocMinStep (a calibrated value, which can be set to 0.1%), then the total number of integration steps is:

[0077]

[0078] Then the SOC value of each integration step can be expressed as:

[0079] SOC n = SOC max -n·SocMinStep;

[0080] where n = 1, 2, 3... N;

[0081] Since there is a one-to-one correspondence between the battery open-circuit voltage OCV and SOC, OCV is a function of SOC:

[0082] OCV n = f(SOC n ) (3)

[0083] In practical engineering applications, generally, the SOC-OCV mapping relationship table obtained through off-line testing is used, and then OCV n is obtained by looking up the table through the real-time SOC n in the BMS software.

[0084] The maximum actual capacity C that the battery can discharge max is also a function of temperature. Similarly, in the BMS software, the maximum actual capacity C at the current temperature is obtained by looking up the table through the real-time temperature Temp n . maxn .

[0085] The allowable depth of discharge DOD of the battery is related to the aging state of the battery. Taking a ternary lithium battery as an example, generally at the BOL stage when the battery is just out of the factory, the DOD range is 97% - 3%, that is, DOD = 94%. As the battery performance further deteriorates, the DOD range will gradually shrink.

[0086] In summary, equations (1) and (2) can be discretized as follows:

[0087]

[0088]

[0089] The above can be understood as: E max is the integral of the area under the SOC-OCV curve from SOC max to SOC min , while E re is the integral of the area under the SOC-OCV curve from the current actual SOC n to SOC min . Then the theoretical remaining energy state of the battery is estimated as:

[0090]

[0091]

[0092] Among them, the above two equations (6) are parallel equalities.

[0093] S205. Obtain the second-order battery equivalent circuit model of the battery to be estimated under the current working condition and the preset first-order inertial filtering algorithm.

[0094] S206. Calculate the actual available power output by the battery and the Joule heat power consumed by the battery internal resistance according to the second-order battery equivalent circuit model.

[0095] S207. Filter the actual available power output by the battery through the first-order inertial filtering algorithm to obtain the filtered actual available power, and filter the Joule heat power consumed by the battery internal resistance through the first-order inertial filtering algorithm to obtain the filtered Joule heat power.

[0096] S208. Calculate the effective energy utilization efficiency of the battery under the current working condition according to the filtered actual available power and the filtered Joule heat power.

[0097] In this embodiment, the method also considers the estimation of the actual energy effective utilization efficiency of the battery considering the actual temperature and working condition. According to the law of conservation of energy, the total energy of the battery = the available energy output by the battery + the Joule heat consumed by the internal resistance of the battery + the reaction heat consumed inside the battery.

[0098] In this embodiment, the reaction heat consumed inside the battery reflects the entropy change of the battery's electrochemical reaction and is mainly affected by the starting and ending SOC. During the actual use of the battery, the actual working condition is mostly medium current intensity and alternating charge and discharge. In this case, the proportion of the reaction heat in the total heat generated by the battery is relatively small and can generally be ignored. Therefore, only the Joule heat consumed by the internal resistance of the battery is considered in this patent.

[0099] In this embodiment, the Joule heat consumed by the internal resistance of the battery is estimated based on the battery equivalent circuit model, as shown in the following figure. According to Kirchhoff's voltage law and Kirchhoff's current law, the state space equation of the first-order RC model is:

[0100]

[0101] U t = U ocv - U P - i L R0 (8)

[0102] It can be seen from the above equation that the product of the terminal voltage U t and the actual current iL flowing through the battery is the actual available power P act = U t · i L , and the Joule heat power consumed by the internal resistance of the battery is jointly reflected by the polarization internal resistance and the ohmic internal resistance. Transforming Equation (8) gives:

[0103] ΔU = U p + i L R0 = U ocv - U t (9)

[0104] Then the Joule heat power consumed by the battery internal resistance heating is:

[0105] P loss = ΔU · i L = (U ocv - U t ) · i L (10)

[0106] Among them, the calculation of ΔU is based on the battery model, and the internal resistance parameter of the model is determined according to the actual temperature, SOC, and current. Therefore, P loss can reflect the heating power consumption under real-time working conditions.

[0107] In summary, the effective energy utilization efficiency of the battery is as follows:

[0108]

[0109] Considering that the real-time voltage and current are complex and variable, if the effective energy utilization efficiency is calculated in real time using the above formula, it will cause a drastic change in the final energy state estimation, which obviously cannot meet the actual usage requirements. Therefore, before performing the K e calculation, P act and P loss can be filtered in real time first. The filtering algorithm can not only smooth the power curve but also have a certain function of predicting the power change trend. In this patent, a first-order inertial filtering algorithm is used to filter the power, and the output of the power filter at time k is:

[0110]

[0111] where Δt is the sampling interval, and T c is the filtering time constant, and the value of the filtering time constant can be determined according to the severity of the actual working condition changes. It can be seen from the above filtering formula that the filtered power at the current time k is related to the current power sampling value P k and the filtered power value P filter_k-1 at the previous time, and the filtering intensity can be adjusted according to the calibration values of T c and Δt. Generally, setting T c >>Δt can obtain a relatively smooth power curve and have the function of remembering the historical power, and have a certain prediction effect on the future power change trend.

[0112] S209. Correct the theoretical remaining energy state of the battery according to the battery effective energy utilization efficiency to obtain the actual remaining energy state of the battery.

[0113] In this embodiment, this method can comprehensively consider the obtained theoretical remaining energy state and the energy effective utilization coefficient to obtain the actual remaining energy state of the battery under the current temperature and working conditions:

[0114] SOE act =K e *SOE pre (13)

[0115] where SOE act is the actual remaining energy state of the battery.

[0116] In this embodiment, the execution subject of the method can be a computing device such as a computer or a server, and no limitation is imposed in this embodiment.

[0117] In this embodiment, the execution subject of the method can also be a smart device such as a smart phone or a tablet computer, and no limitation is imposed in this embodiment.

[0118] It can be seen that implementing the battery remaining discharge energy estimation method described in this embodiment can consider the influence of the actual temperature and working conditions on the dischargeable energy of the battery; specifically, this method can accurately estimate and implement the actual remaining available energy state of the battery by combining the estimation of the theoretical remaining energy state of the battery SOC-OCV curve area integration and the influence of the actual temperature working conditions on the energy effective utilization rate, thereby simplifying the engineering application.

[0119] Embodiment 3

[0120] Please refer to Figure 3 , Figure 3 , which is a schematic structural diagram of a battery remaining discharge energy estimation device provided in this embodiment. As Figure 3 shown, the battery remaining discharge energy estimation device includes:

[0121] A first acquisition unit 310, configured to acquire the maximum available capacity of the battery to be estimated at the current temperature, the current battery SOC of the battery to be estimated, the DOD range allowed for the battery to be estimated to operate in the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature;

[0122] A calculation unit 320, configured to calculate the theoretical remaining energy state of the battery according to the current battery SOC, DOD range, battery maximum available capacity, and battery open-circuit voltage curve;

[0123] A second acquisition unit 330, configured to acquire the battery effective energy utilization efficiency of the battery to be estimated under the current working conditions;

[0124] A correction unit 340, configured to correct the theoretical remaining energy state of the battery according to the battery effective energy utilization efficiency to obtain the actual remaining energy state of the battery.

[0125] In this embodiment, the explanation of the battery remaining discharge energy estimation device can refer to the description in Embodiment 1 or Embodiment 2, and no further elaboration will be provided in this embodiment.

[0126] It can be seen that implementing the battery remaining discharge energy estimation device described in this embodiment can consider the influence of the actual temperature and working conditions on the dischargeable energy of the battery. Specifically, this method can accurately estimate the actual remaining available energy state of the battery by combining the estimation of the theoretical remaining energy state based on the area integration of the battery SOC-OCV curve and the influence of the actual temperature working conditions on the energy utilization efficiency, thereby simplifying the engineering application.

[0127] Embodiment 4

[0128] Please refer to Figure 4 , Figure 4 which is a schematic structural diagram of a battery remaining discharge energy estimation device provided in this embodiment. As Figure 4 shown, the battery remaining discharge energy estimation device includes:

[0129] A first acquisition unit 310, configured to acquire the maximum available capacity of the battery to be estimated at the current temperature, the current battery SOC of the battery to be estimated, the DOD range allowed for operation of the battery to be estimated in the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature;

[0130] A calculation unit 320, configured to calculate the theoretical remaining energy state of the battery according to the current battery SOC, DOD range, maximum available capacity of the battery, and the battery open-circuit voltage curve;

[0131] A second acquisition unit 330, configured to acquire the battery effective energy utilization efficiency of the battery to be estimated under the current working conditions;

[0132] A correction unit 340, configured to correct the theoretical remaining energy state of the battery according to the battery effective energy utilization efficiency to obtain the actual remaining energy state of the battery.

[0133] As an optional implementation manner, the first acquisition unit 310 includes:

[0134] A first acquisition subunit 311, configured to acquire the current temperature of the battery to be estimated, the current battery SOC of the battery to be estimated, the DOD range allowed for operation of the battery to be estimated in the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature;

[0135] A second acquisition subunit 312, configured to acquire the maximum available capacity of the battery at the current temperature according to a preset battery capacity table.

[0136] As an optional implementation manner, the calculation unit 320 includes:

[0137] The first calculation subunit 321 is configured to perform area integration calculation on the battery open-circuit voltage curve according to the current battery SOC, DOD range, and the maximum available capacity of the battery, so as to obtain the theoretical maximum discharge energy and the theoretical remaining available discharge energy;

[0138] The second calculation subunit 322 is configured to calculate the theoretical remaining energy state of the battery according to the theoretical maximum discharge energy and the theoretical remaining available discharge energy.

[0139] As an alternative implementation manner, the second acquisition unit 330 includes:

[0140] The third acquisition subunit 331 is configured to acquire the second-order battery equivalent circuit model of the battery to be estimated under the current working condition and a preset first-order inertial filtering algorithm;

[0141] The third calculation subunit 332 is configured to calculate the actual available power output by the battery and the joule heat power consumed by the battery internal resistance according to the second-order battery equivalent circuit model;

[0142] The third calculation subunit 332 is further configured to calculate the effective energy utilization efficiency of the battery under the current working condition according to the first-order inertial filtering algorithm, the actual available power output by the battery, and the joule heat power consumed by the battery internal resistance.

[0143] As an alternative implementation manner, the third calculation subunit 332 includes:

[0144] A filtering module is configured to perform filtering processing on the actual available power output by the battery through the first-order inertial filtering algorithm to obtain the filtered actual available power, and perform filtering processing on the joule heat power consumed by the battery internal resistance through the first-order inertial filtering algorithm to obtain the filtered joule heat power;

[0145] A calculation module is configured to calculate the effective energy utilization efficiency of the battery under the current working condition according to the filtered actual available power and the filtered joule heat power.

[0146] In this embodiment, the explanation of the battery remaining discharge energy estimation device may refer to the descriptions in Embodiment 1 or Embodiment 2, and thus will not be elaborated herein.

[0147] It can be seen that implementing the battery remaining discharge energy estimation device described in this embodiment can consider the influence of the actual temperature and working conditions on the dischargeable energy of the battery; specifically, this method can accurately estimate and implement the actual remaining available energy state of the battery by combining the estimation of the theoretical remaining energy state of the battery SOC-OCV curve area integration and the influence of the actual temperature working conditions on the energy effective utilization rate, thereby simplifying the engineering application.

[0148] An embodiment of the present application provides an electronic device, including a memory and a processor. The memory is used to store a computer program, and the processor runs the computer program to enable the electronic device to execute the battery remaining discharge energy estimation method in Embodiment 1 or Embodiment 2 of the present application.

[0149] An embodiment of the present application provides a computer-readable storage medium, which stores computer program instructions. When the computer program instructions are read and run by a processor, the battery remaining discharge energy estimation method in Embodiment 1 or Embodiment 2 of the present application is executed.

[0150] In several embodiments provided by the present application, it should be understood that the disclosed device and method can also be implemented in other ways. The device embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the drawings show the possible architectures, functions, and operations of devices, methods, and computer program products according to multiple embodiments of the present application. In this regard, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and the combination of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0151] In addition, in each embodiment of the present application, the functional modules can be integrated together to form an independent part, or each module can exist alone, or two or more modules can be integrated to form an independent part.

[0152] When the above-mentioned functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of this application. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs.

[0153] The above are only the embodiments of this application and are not used to limit the protection scope of this application. For those skilled in the art, this application can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of this application shall be included in the protection scope of this application. It should be noted that similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0154] As mentioned above, this is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by this application and should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

[0155] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitations, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

Claims

1. A method for estimating the remaining discharge energy of a battery, characterized in that, Including: Obtain the maximum available capacity of the battery to be estimated at the current temperature, the current battery SOC of the battery to be estimated, the DOD range allowed for the battery to be estimated to operate in the current aging state, and the open-circuit voltage curve of the battery to be estimated at room temperature; Calculate the theoretical remaining energy state of the battery according to the current battery SOC, the DOD range, the maximum available capacity of the battery, and the open-circuit voltage curve of the battery; Obtain the battery effective energy utilization efficiency of the battery to be estimated under the current working condition; Correct the theoretical remaining energy state of the battery according to the battery effective energy utilization efficiency to obtain the actual remaining energy state of the battery; Among them, the obtaining of the maximum available capacity of the battery to be estimated at the current temperature, the current battery SOC of the battery to be estimated, the DOD range allowed for the battery to be estimated to operate in the current aging state, and the open-circuit voltage curve of the battery to be estimated at room temperature includes: Obtain the current temperature of the battery to be estimated, the current battery SOC of the battery to be estimated, the DOD range allowed for the battery to be estimated to operate in the current aging state, and the open-circuit voltage curve of the battery to be estimated at room temperature; Obtain the maximum available capacity of the battery at the current temperature according to a preset battery capacity table; Among them, the calculating of the theoretical remaining energy state of the battery according to the current battery SOC, the DOD range, the maximum available capacity of the battery, and the open-circuit voltage curve of the battery includes: Perform area integration calculation on the open-circuit voltage curve of the battery according to the current battery SOC, the DOD range, and the maximum available capacity of the battery to obtain the theoretical maximum discharge energy and the theoretical remaining available discharge energy; Calculate the theoretical remaining energy state of the battery according to the theoretical maximum discharge energy and the theoretical remaining available discharge energy.

2. The battery remaining discharge energy estimation method according to claim 1, wherein The obtaining of the battery effective energy utilization efficiency of the battery to be estimated under the current working condition includes: Obtain the second-order battery equivalent circuit model of the battery to be estimated under the current working condition and a preset first-order inertial filtering algorithm; Calculate the actual available power output by the battery and the Joule heat power consumed by the battery internal resistance according to the second-order battery equivalent circuit model; Calculate the battery effective energy utilization efficiency under the current working condition according to the first-order inertial filtering algorithm, the actual available power output by the battery, and the Joule heat power consumed by the battery internal resistance.

3. The method for estimating the remaining discharge energy of the battery according to claim 2, wherein The calculating of the battery effective energy utilization efficiency under the current working condition according to the first-order inertial filtering algorithm, the actual available power output by the battery, and the Joule heat power consumed by the battery internal resistance includes: Perform filtering processing on the actual available power output by the battery through the first-order inertial filtering algorithm to obtain the filtered actual available power, and perform filtering processing on the Joule heat power consumed by the battery internal resistance through the first-order inertial filtering algorithm to obtain the filtered Joule heat power; Calculate the battery effective energy utilization efficiency under the current working condition according to the filtered actual available power and the filtered Joule heat power.

4. A device for estimating the remaining discharge energy of a battery, characterized in that, The battery remaining discharge energy estimation device includes: A first acquisition unit, configured to acquire the maximum available capacity of the battery to be estimated at the current temperature, the current battery SOC of the battery to be estimated, the DOD range allowed for operation of the battery to be estimated in the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature; A calculation unit, configured to calculate the theoretical remaining energy state of the battery according to the current battery SOC, the DOD range, the maximum available capacity of the battery, and the battery open-circuit voltage curve; A second acquisition unit, configured to acquire the battery effective energy utilization efficiency of the battery to be estimated under the current working condition; A correction unit, configured to correct the theoretical remaining energy state of the battery according to the battery effective energy utilization efficiency to obtain the actual remaining energy state of the battery; Wherein, the first acquisition unit includes: A first acquisition subunit, configured to acquire the current temperature of the battery to be estimated, the current battery SOC of the battery to be estimated, the DOD range allowed for operation of the battery to be estimated in the current aging state, and the battery open-circuit voltage curve of the battery to be estimated at room temperature; A second acquisition subunit, configured to acquire the maximum available capacity of the battery at the current temperature according to a preset battery capacity table; Wherein, the calculation unit includes: A first calculation subunit, configured to perform area integration calculation on the battery open-circuit voltage curve according to the current battery SOC, the DOD range, and the maximum available capacity of the battery to obtain the theoretical maximum discharge energy and the theoretical remaining available discharge energy; A second calculation subunit, configured to calculate the theoretical remaining energy state of the battery according to the theoretical maximum discharge energy and the theoretical remaining available discharge energy.

5. An electronic device, characterized in that, The electronic device includes a memory and a processor, the memory is used to store a computer program, and the processor runs the computer program to enable the electronic device to execute the battery remaining discharge energy estimation method according to any one of claims 1 to 3.

6. A readable storage medium, characterized in that, Computer program instructions are stored in the readable storage medium, and when the computer program instructions are read and run by a processor, the battery remaining discharge energy estimation method according to any one of claims 1 to 3 is executed.

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